Question

How can i fetch 192.168.1.101 usin regex in java in following string ,however Bcast may be or not present

'      inet addr:192.168.1.101  Bcast:192.168.1.255  Mask:255.255.255.0'

with leading space

Answer 1

Use something like this:

(?<=inet addr:)\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}

I really feel Abhishek Simon’s answer for the regex is an overkill. You are just extracting, not validating if it is a legal IP address!

For Bcast use something like below, obviously:

(?<=Bcast:)\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}

To get all IPs, use without the initial lookahead.

You might be better of doing some string operations like splitting on and : to get the IPs. I leave it to you to decide.